JPS61126800A - Cordless movable x-ray device - Google Patents

Abstract

PURPOSE:To correct voltage variation in an X-ray tube due to variation of internal resistance in a battery so as to enable to take an X-ray photograph with good reproducibility by detecting battery voltage while the battery is connected to a preset load and changing output voltage of an inverter circuit depending on the detected voltage. CONSTITUTION:As a manual switch 13 is pushed to the first step, positive pole driving circuit 11 operates, the positive pole of an X-ray tube device begins to rotate, and a timing circuit 21 starts operation. Now the internal resistance of the battery 1 has changed by the amount equivalent to pass positive pole driving current, and the terminal voltage of the battery drops proportionally to the change in the resistance. The battery voltage is readout by a detecting circuit 22 which operates synchronously with the signal generated by a timing circuit 21 after a preset time elapsed. The readout battery voltage is compared with a standard voltage through a comparator circuit 23, and optimum output voltage predetermined to a best shot condition from an inverter circuit is set by a voltage switching device 3. After these conditions are fulfilled, as the second step of the manual switch 13 is pushed, the voltage variation in the X-ray tube resulting from variation in the internal resistance of the battery is corrected and X-rays are emitted.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to an X-ray tube voltage correction circuit for a mobile X-ray device using a battery as a source, and particularly relates to an X-ray tube voltage correction circuit for a mobile X-ray device using a battery as a source. The present invention relates to an X-ray tube voltage correction circuit suitable for correcting tube voltage fluctuations.

[Background of the invention]

2. Description of the Related Art Conventionally, it has been known to use a battery to supply electricity to an X-ray apparatus, and to make the apparatus mobile.

As mentioned above, this type of device uses the Batch IJ+ as a power source for the X-ray generator, and is movable, so it can be used to take X-ray photographs in places where there is no power source for the X-ray device. The advantage is that the device can be moved and used conveniently even in cases where the subject cannot be moved.

However, in the conventional device described above, the voltage between the terminals of the battery decreases due to the increase in internal resistance due to the discharge of the battery due to X-ray radiation and movement of the device, or due to natural discharge of the battery. There is a disadvantage that the X-ray tube voltage also decreases accordingly.

In addition, even in devices that detect battery voltage and correct X-ray tube voltage, they only detect the voltage between one terminal of the battery when there is no load, so Correction of tube voltage was not possible.

For the above reasons, this type of X-ray equipment has a slow re-limitability.
The drawback was that it was impossible to take line photographs.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a cordless mobile X-ray device that corrects X-ray tube voltage fluctuations caused by changes in internal resistance due to battery discharge, and is capable of taking X-ray photographs with good repeatability. .

[Summary of the invention]

The present invention teaches that when a constant load is connected to a battery, the voltage across one terminal of the battery drops in proportion to the change in its internal resistance, and that Xl1l! We focused on two points: during imaging, it is necessary to rotate the anode of the X-ray tube device (referred to as rotor up) before the X-ray is emitted, and it takes a certain amount of time for the anode to reach a steady rotation speed. It was made by

That is, the feature of the present invention is that while a certain load (for example, a load for anode drive) is connected to the battery,
After detecting the battery voltage at a certain timing and changing the output voltage of the inverter circuit according to the detected voltage to reduce changes in the X-ray tube voltage due to changes in the battery's internal resistance, It is at the point where it radiates.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 shows the circuit configuration of the embodiment. 1 is a battery that is the power source of the device, 2 is an inverter circuit that converts the DC power supplied by the battery to AC, 3 is a switch for the output voltage from the inverter, 4 is a transformer, and 5 is an X-ray tube voltage setting device. , 6 is X? This is a high pressure generator that applies high pressure to the s-tube device 7. Also, an anode drive circuit 11 for driving the anode of the X-ray tube device, and a control circuit 1 for controlling these circuits.
2. A two-stage motion hand switch 13 for X-ray radiation, a timing circuit 21 that sets the timing of battery voltage detection, a battery voltage detection circuit 22, and compares its output with a reference value to determine the output voltage of the inverter circuit 2. A comparison circuit 23 is provided. Although not specifically described here, it goes without saying that the X-ray control device is equipped with a timer circuit, an X-ray tube filament heating circuit, and the like.

Next, the operation of the circuit will be explained. When the hand switch 13i is pressed to the first stage (denoted as IH8), the anode drive circuit 11 is activated, the anode of the X-ray tube device 7 begins to rotate, and the timing circuit 21 begins to operate. At this time, the internal resistance of the battery 1 changes as much as the anode drive current (mainly) is applied, and the voltage between the terminals of the battery drops in proportion to this change. This voltage is read by operating the detection circuit 22 in synchronization with a signal generated by the timing circuit 21 after a set time has elapsed. The read battery voltage is compared with a reference voltage in the comparator circuit 23, and the output voltage from the inverter circuit is set by the switch 3 that is optimal for the set photographing conditions. When the second step (denoted as 2H8) of the hand switch 13 is pressed in this state, the X-ray tube voltage fluctuation caused by the internal resistance change of the battery is corrected and X-ray radiation is performed. The time chart for this period is shown in the second
As shown in the figure. Among the above operations, 1 of the hand switch 13
．． Even if the second stage is pressed at the same time, there is no problem because X-rays will not be emitted until the anode of the X-ray tube reaches a steady rotation speed, and the output voltage of the inverter circuit can be set as described above during this time. . Also, in this figure, the switch 3 is installed on the primary side of the transformer 4, but the same operation can be achieved even if it is installed on the secondary side, and as a voltage switching method, the inverter can operate without using a switch. It is natural that measures such as changing responsibilities can be taken.

[Effects of the Invention] According to the present invention, X due to changes in internal resistance of the battery
Since fluctuations in the tube voltage can be corrected, it is possible to take X-ray photographs with good redefinability.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, and FIG. 2 is a time chart. 1...Battery, 2...Inverter circuit, 3...
・Voltage switcher, 4...Transformer, 5...Tube voltage setting device, 6...High pressure generator, i...X-ray tube device, 21...
- Timing circuit, 22...Battery voltage detection circuit, 23...Comparison circuit.

Claims (1)

[Claims] 1. A power battery, an inverter circuit that converts the DC power supplied by the battery into AC, a high voltage transformer that boosts the output voltage of the inverter circuit, and an X that emits X-rays by applying the high voltage. In a cordless mobile X-ray device consisting of a ray tube device, means is provided for detecting the voltage of the power supply battery under a constant load at a timing immediately before X-ray emission, and the detected value is compared with a set value by a means. A cordless mobile X-ray apparatus characterized in that even if the internal resistance of the battery changes, fluctuations in the X-ray tube voltage are reduced by means for comparing the output voltage of the inverter circuit and correcting the output voltage of the inverter circuit based on the comparison result.